Session R4J Mechanical Engineering Curriculums Using CAED

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1 Curriculums Using CAED Vijay K. Goyal and Ricky Valentin Department of University of Puerto Rico at Mayagüez Mayagüez, PR Abstract. Advances in engineering simulation software have resulted in a significant shift in the engineering design process of industries. However, engineering education has not adjusted well to take advantage of these new design and analysis tools within the curriculum. Consequently, there is currently a significant disconnect between what universities provide for mechanical engineering education and what industry needs from the graduating students. This paper examines some of the issues surrounding the use of computers in the design, analysis, and manufacturing aspects in the educational environment. These concepts are currently being integrated into the Computer- Aided Design (CAED) at the ME Department at the University of Puerto Rico as the CAED course has being redesigned to fit the 21 st century Engineer. It is a balanced blend of theory, applications and the use of commercially available computer software. As part of this innovative CAED course, a mechanical engineering design project is worked in teams of 3-4 students throughout the course of the project. Students not only acquire the technical knowledge but improve their skills in team-working, proposal and report writing, and presentation skills. This paper includes a proposed model for the integration of these techniques into most courses. INTRODUCTION Computer aided design was first taught in Australia in 1967 at the University of Sydney. The intention of that first course was to describe new products as one graphical object in the final phases of design (Björk, 1989). Drawings were done only with simple lines and objects were assembled from several separate short lines (Eastman, 1991). Mitchell (1977) taught already at the end of the seventies that during the 1980 s everyday use of computer aided design techniques would radically transform the practice of design. However, for a long period of time the programs were very difficult and awkward to use despite their steady development. By the beginning of the 1980 s, programs were good enough to aid in the teaching of design in universities. At the same time, Computer Aided (CAE) was advocated in the United States as a means of supplying analysis information in a timely manner in the design and manufacturing fields, thereby enabling huge improvements to be made to existing products through the application of unprecedented new techniques (Lemon, 1980). However, it is in the 1990 s, that the development of the computational resources achieved that reality. Similarly, design applications software was applied to traditional curriculums (Achten, 1996). The main problem with the implementation of CAE in traditional curriculums is that it was much faster than the research in applied design methods. In addition, rigidities and inconveniences in applications have caused negative attitudes towards CAE by professors. There is however development, but not always in the scientific sense. Among the ideas in design methods derived from that is Concurrent, which appeared at the beginning of the 1990s. This advocated a change from the normal approach in which development processes such as product design, testing, and manufacturing were sequential, to situation in which the processes overlapped. We have seen cases in which the use of Concurrent, as typified by design and production techniques such as Design for X (Boothroyd, 1994) and Agile Manufacturing (Goldman, 1993) enables the commercialization of products in a very short time. Using these capabilities, design engineers can execute CAE while performing drawing with CAD. We now have access to an environment in which individual design engineers can handle advanced CAE at the design stage. The commercialization of new electronic devices, which undergo model changes every few months, is an excellent example of this. These cases can be regarded as successful attempts to apply CAE to the prototype, experiment, and evaluation stages, backed by recent improvements in computer hardware (Kojima, 2000). THE CASE FOR CHANGES Computer aided design is a young discipline in science, but CAED has a significant domain in practical development. Due to the short and changing history of CAED, Gero and Maher (1997), a question has been posed: what directions are open for design computing education? Not so much what projects should be pursued, rather what strategic directions may yield results, which inform us about designing and produce processes of value. Such knowledge will have implications for both how CAED can be interfaced with human designers and, perhaps more importantly, provide new conjectures for design computing research to explore in order to provide the foundation for more useful tools for designers. Similarly, as the other approaches yield insights into designing they may provide the foundation for novel tools. R4J-22

2 Sorby et al. states that the mechanical engineering curriculum found at most universities has not changed enough in the recent past to adequately reflect the new design/analysis/ manufacturing paradigm which exists in industry today. The engineering curricula has evolved over the years to include some computer applications, but computer techniques for the most part are not an integral and pervasive part of the curriculum as they are in the industrial sector. Industry needs from academia to teach students so that they are prepared to be productive as soon as they graduate. Students need from academia an education that will make them marketable for their first job and successful for their entire career. A solid foundation in computer aided design/analysis/manufacturing within the mechanical engineering curriculum will satisfy the needs and desires of both industry and students. Some of Sorby et al. ideas are that the software will: 1. enhance learning in other courses; i.e., they can be used as a teaching aid in other courses, 2. provide students with a more real-world experience similar to that of engineers in industry, 3. increase complexity of problems, 4. show students the necessity of thinking ahead that there may be consequences downstream for design choices that they make early in the process, 5. be effectively used for distance learning, and 6. allow faculty to develop the analytical and/or design skills necessary to do applied research. Let s consider the case of a curriculum in the University of Puerto Rico at Mayaguez (UPRM) as an example, which is highlighted with its main features in Table 1. Our engineers in Puerto Rico are employed in many areas, but most of them are absorbed in manufacturing and in process industries working as maintenance engineers, production engineers, product developers, designers, sales engineers etc. The manufacturing and process industries produce goods that go into the market. The goods have to be competitive as otherwise they will not get a market share. Table 2 gives a summary of the attributes of the graduate mechanical engineer when compared to requirements of the work environment. It is apparent that the mechanical engineering training is highly technology centered and misses important knowledge areas necessary for competitive product development as reflected in Table 2. Neither the mechanical engineering graduate nor the graduates in the other engineering fields at UPRM trained in the traditional way is adequately prepared for the emerged competitive market. Experience shows that the engineers learn the missed skills the hard way, through experience on the job. He/She is liable to gain inadequate knowledge and also learn bad habits. In addition, our mechanical engineers are expected to handle most of product design/development tasks in the industries. Depending of the nature of the industry, he/she may work together with a process engineer, a chemical engineer or an electrical engineer. In order to address the need to equip our graduates with knowledge and skill for competitive product development, the curriculum has to be enhanced so that students are trained on an integrated approach to product development. FEATURES OF THE NEW ENHANCED CURRICULUM Computer aided design is a young discipline in science. Its key issues, however, have been discussed within a number of related disciplines. These areas may be, and have been, far away from design theory, even when they should contain it. It is therefore useful to summarize those lines of research and development that have addressed computer aided design. This is, in practice, an impossible task, because almost all linked disciplines have a large body of literature in the background discussing either directly or indirectly the topic of this research. It is, however, possible to point out some lines of research that have direct relevance to this research (Fig. 1). This outline may not be the only and final way to see the factors behind CAD, but the purpose of this outline is to analyze the theoretical framework, which is useful to the researcher. Sorby (1999) mentioned that to implement computer usage effectively throughout the curriculum, it is important that the design/analysis/manufacturing software be fully integrated. The primary advantage of this is that faculty and students will not have to spend countless hours learning several different software packages and hardware platforms, but will be able to learn one package that they can then apply to several different problems. The idea presented in this paper is designed to address industry's increased needs for engineers in these areas who can model complex engineering design and analysis problems competently using computers. It will prepare today's engineers to be experts in various aspects of computer-aided engineering. The emphasis will be on fundamentals of analysis and design and the use of commercially available computer codes such as ProEngineer, ANSYS, PATRAN, and ABAQUS. The purpose of this new idea in mechanical engineering is to enable engineers to become excellent in a computer-aided design field without formally pursuing a graduate degree. The idea of a modern computer-aided engineering design course is that it will provide a core set of integrated fundamentals of design, analysis, the finite element analysis, and CAD/CAM applications. The students take this course after taking related courses either in mechanical systems or thermal/fluid systems. Students completing the course will be able to understand the theoretical foundations of the modeling and analysis of various mechanical components and their performance analysis. The core module of the idea on computational methods include the finite element method and computational fluid dynamics themes which may serve as a foundation to computer simulations in other multidisciplinary R4J-23

3 fields such as biomechanics, mechatronics, nanotechnology, and computational physics. The course presented in this paper is a self-contained course, with an integrated tutorial for MatLab and ANSYS. We present many pedagogical lessons that reinforce the value of working from the most basic principles and using the necessary technology as a tool and not as a substitute for good engineering. Each module in class begins with instructional objectives and ends with a summary highlighting the most important aspects of the module. The course s emphasis is on improving design and development of engineering systems by employing simulation and optimization techniques using MatLab and ANSYS. Of special interest are systems that combine several fields of engineering such as structural, fluid dynamics, electrical and thermal subsystems. In order to support these scenarios, the course focuses on three basic parts inherent in these scenarios, which are: (1) design, (2) optimization, and (3) simulation. The goal is for students to apply all the learned concepts in a well-work student project throughout the course. In the first part of the course, we explore issues that will ensure an efficient design process. In here, we present a mathematical review of linear algebra and calculus using MatLab. Lecture notes are provided with a self-contained introduction to MatLab. In addition, lecture notes introduction to technical communications are also provided, with an outlined step-bystep throughout the semester project. This encourages students to not only engage in classroom learning but to also incorporate pedagogical lessons into a real-world problem. At the end, it is recommended that students give an oral presentation of their final design project. Electronic templates for written submissions by students are available for students as a guide. The second part of the course, involves an in-depth introduction to engineering optimization. This part of the course provides introductory tools for the engineer to be able to optimize the system with the help of the mathematical tools presented in the first part of the course. This part of the course covers the most important topics with the purpose to motivate student to continue studying the subject further, by taking an advanced optimization course. By the end of this part, students should feel comfortable to open most optimization textbooks and be able to follow through with the concepts presented in the course. In the third part of the course, we look at the general principles of the finite element analysis method. The purpose of this part is to provide engineers with tools and methods which support systems design and analysis. We begin with simple spring analysis to help the student grasp the concepts regarding stiffness matrices and their assembly. Then we generalize the method using energy principles. For students not familiar with variational principles, a short self-contained course in Variational Calculus is included in lecture notes. Methods discussed in this part include powerful modeling and simulation tools suitable for large multi-domain systems. An important aspect of the course is the last part of the course, which applies the concepts, learned throughout the course and applied them in ANSYS: design, analysis and optimization. For students not familiar with ANSYS, we provide a self-contained crash course in getting familiar with ANSYS. The course ends with exciting applications in several fields of engineering such as structural, fluid dynamics, electrical and thermal subsystems. POSSIBLE FUTURE SCENARIOS Competency requirements of engineers in Puerto Rico have expanded from the traditional Technology Centered to Customer centered engineering. The expansion has been a result of new developments in technology and also competitiveness of the modern Puerto Rican market due to the forces of the free market economy. Attempt has been made to address these developments by introducing elements of design optimization into the traditional programs of. Examining the curriculum, it can be observed that there is relatively more coverage on the aspects of innovation management and less on the other aspects of complex design. Because of the strong impact on acceptability of products, more need to be done to improve the curriculum on the areas of CAED. CONCLUSION Computer tools have become an essential part of modeling, analysis, and design in engineering practice. With the advent of fast and powerful computers, it is expected that decisions in engineering and sciences will be based upon computational simulations that will be of unprecedented magnitudes, size, scope, and complexity. With the advances in computers there have been a great deal of advances in the field of computeraided engineering where engineers are required to routinely solve complex problems in fluid mechanics, heat and mass transfer, structural mechanics, vibrations, and acoustics. Most of these problems require the use of computational tools such as solid modelers, computer-aided design and computer-aided manufacturing (CAD/CAM) systems, system simulators, and finite element simulation codes. Engineers who use commercial codes for design and analysis must be highly proficient with mathematical and computational aspects of the methods involved as well as the physical principles associated with these phenomena. The idea has been incorporated in selected engineering programs at UPRM so as to enhance skills for competitive product development. The new generation of mechanical engineers graduating from UPRM, for example, are multiskilled, with competencies in traditional mechanical engineering, computer assisted technologies, and techniques for competitive product development. However, opportunities to improve the curriculum still exist. R4J-24

4 REFERENCES Achten H (1996). Teaching Advanced Architectural Issues Trough Principles of CAAD, Proceedings ECAADE 14th Conference of Education of Computer Aided Architectural Design in Europe, Lund, Sweden, Björk, B-C (1989). Basic Structure of a Proposed Building Product Model, Computer-Aided Design 21(2): Boothroyd, G. Product Design for Manufacture and Assembly, Marcel Dekker, New York, USA, Eastman, CM (1991). The Evolution of CAD: Integrating Multiple Representations, Building and Environment 26(1): Gero, JS, Maher, ML (1997) A Framework for Research in Design Computing, Proceedings 15 th Conference of Education of Computer Aided Architectural Design in Europe, Vienna, Austria, CD-ROM. Goldman, SL, Nagel, RN, Preiss, K. Agile Competitors and Virtual Organisations: Strategies for Enriching, VanNostrand Reinhold, UK, Haapasalo, H (1977). An internal approach to the design process. Dissertation from University of Oulu, Kojima, Y. (2000) CAE in Automotive Design, R&D Review of Toyota CRDL, 35 (4). Medland AJ, and Mullineux G Principles of CAD. Billing and Sons Ltd, London, UK, Mitchell, WJ Computer aided architectural design. Van Nostrand Reinhold, New York, USA, Nalitolela, NG Development of Industrial Design at the University of Dar es Salaam, International Conference on Industrial Design UDSM, DAR ES SALAAM, JULY 17-18, 2003 Schmitt G Micro Computer Aided Design for Architects and Designers. John Wiley & Sons Inc, New York, USA, Sorby, S, Walker, G, Yano, M, Glozman, V, Kochersberger, K, Mathers, J, McKinney, J, Schulman, J, Young, M, (1999) Modernization of the Curriculum and Guidelines for Computer-Aided Instruction, Computer Applications in Education, 7 (4). Takezawa A, Nishiwaki, S, Izui K, Yoshimura, M, Nishigaki, H, Tsurumi, Y (2005). Concurrent Design and Evaluation Based on Structural Optimization using Structural and Function-oriented Elements at the Conceptual Design Phase, Concurrent, 13 (1), Table 1: Overview of curriculum at UPRM Year One Year Two Year Three Year Four Year Five Computer Aided Drafting (AutoCAD) Basic Foundation including Intro to Computers and programming, Workshop training, industry + Development studies including introduction to electronics & electrical machines, and industry Fundamentals of Electrical including, industry Computer Aided Design and Manufacture Subjects and final year Project. R4J-25

5 S/N 1 2 Table 2: Skill/knowledge requirements for competitive product development Skills/Knowledge Requirement for Competitiveness Technical Manufacturing Technology Materials Technology Non Technical Assessment of Knowledge/Skill Gained by a Eng. at University Excellent Excellent only on metallic materials 3 Thermodynamics Excellent 4 Heat Transfer Excellent 5 Machine Design Excellent 6 Mechanics Excellent 7 Computer skills Excellent 8 CAD/CAM Excellent 9 Management Excellent 10 Excellent 11 Packaging None 12 Styling/Aesthetics None 13 Product Ergonomics 14 Competition Analysis None 15 Pictorial Free Hand Drawing None 16 Marketing None 17 Innovation Techniques None 18 Packaging Design None 19 Analytical Skills Excellent only on mathematical analysis Figure 1. The analysis framework of the theory and literature of this research. Note: there is no closed loop or area, which means that there is some theory diffusion between topics and the possibility to attain more. (Haapasalo, 2000) R4J-26